If you are a living, breathing human being between the ages of four and 110, then it's almost a certainty that at some point this month, you'll be going to see "Iron Man Three." And not just once but probably several times.

That's because every Marvel film seems to be jam-packed with secret references, hidden jokes and insider Easter eggs designed to thrizzle even the most jaded movie or comic book fan. Forget that RunPee app that tells you when it's safe to leave the theater; in "Iron Man Three," every single second could hold an encrypted message teasing "Howard the Duck 2" or hinting at a crossover with Daredevil or something. Seeing "Iron Man Three" just once simply isn't an option; after all, it's more than a movie, it's a pop culture test you have to study for.

So in order to help you get the most out of your second trip to the theater, we've put together a guide to 7 Things You May Have Missed the First Time Around in "Iron Man Three." Because you don't want to be the one with Easter egg on your face.

1. Dr. Yinsen Lives!

The film begins with a flashback to a 1999 conference in Bern, Switzerland, where Tony briefly meets and then blows off two fellow scientists, Dr. Yu and Dr. Yinsen. Dr. Yu has been getting most of the press, since his character is part of the film's China-only expanded release, but it's Dr. Yinsen who is of real interest to "Iron Man" fans. That's because Yinsen (Shaun Toub) is actually the same guy who saved Tony Stark's life at the beginning of the first "Iron Man" film back in 2008! Not only that, but in "Iron Man," Yinsen actually makes a direct reference to having met Stark previously at a conference in Bern, making the entire opening sequence of "Iron Man Three" one giant Easter egg. Now that's how you do it.

2. Just Who Is Tony Talking To?

In that opening sequence, we also get a voiceover from Robert Downey, Jr., who literally sets the scene for the movie by telling us the tale of everything that went down. But is he actually telling this story to us, the audience ... or is he talking to someone else? If you stick around for the credits, you'll find out the answer, because in one of Marvel's patented "secret" post-credit scenes, we discover that Tony is really telling the story to ... Dr. Bruce Banner (Mark Ruffalo) himself! It's a nice callback to the end of "Marvel's The Avengers," where the two of them drove off into the sunset together.

3. The Credits That Will Not End

Oh, and speaking of those credits, holy smokes. We thought they would literally never end. But there's a pretty good reason for that: Marvel is screwing with us. Knowing that fans would be sticking around to watch the credits, the producers dragged them out for a full ten minutes, listing not only every single person who even thought about working on the film, but some completely fictional crew members as well. Just check out the giant wall of text that comes up when they get to the special effects department and you'll notice at least one patently bogus name: Gwyneth Waltrow. How many other inside jokes are hidden in the credits? You'll have to watch them again and play your own game of Where's Waltrow? to find out.

4. The Hulkbuster

At the climax of the film, Tony unleashes a veritable army of Iron Man suits. But while most of those suits barely get more than a brief cameo, one suit of armor in particular gets an extended closeup, as an immense Iron Man prototype comes running out of nowhere to hoist up a massive crane on its broad shoulders. In fact, the armor is so big and so strong, it resembles nothing so much as a metallic version of The Hulk — which is no coincidence at all, as the design is clearly based on Iron Man's Hulkbuster armor from the comics, which he created explicitly to fight and defeat The Hulk. So does the existence of the Hulkbuster suit presage a showdown between Stark and Banner in an upcoming movie? We sure as hell hope so!

5. Stan Lee, Cameo Artist

Spotting the cameo of Marvel's Chairman Emeritus Stan Lee has become a bit of a ritual for Marvel movie fans, as the legendary co-creator of Iron Man has made brief appearances in nearly every single superhero film based on Marvel characters in the past 15 years. Some are bigger than others, though, and this time around you may miss it if you're distracted — by, for instance, the beauty pageant swimsuit competition he's judging. Hey, what can you say — the ladies love Stan Lee as much as everyone else does.

6. The Secret of Modern Art

In previous installments of the "Iron Man" franchise, some of the coolest Easter eggs have been hidden in plain sight inside Tony Stark's high-tech lab (think Captain America's shield in the first two "Iron Man" films). And this time around is no different. Case in point: That weird big ball of twisted metal sitting in the background? It might appear to just be a random chunk of modern art, but look a little closer and you'll see that it's actually the mangled remnants of the Formula One race car Tony drove in "Iron Man 2." Nothing like a two-ton souvenir, right?

7. Giant-Size Man-Thing

Though the movie is technically about Iron Man, a great deal of its DNA actually comes from a very different Marvel character: the mysterious Man-Thing. In the comics, you see, the cult hero called Man-Thing was originally a scientist who was doing top secret research on plants in the Everglades when his wife betrayed him to AIM. In desperation, he injected himself with his untested formula, only to discover it had seriously unexpected consequences. All of that, of course, is in "Iron Man Three," with AIM using a formula based on plant research to give people superpowers. Need more? Well, how about this: The female AIM agent (played by Stephanie Szostak) who battles Tony to the death midway through the film is named Ellen Brandt, who is best known to comics fans as Man-Thing's treacherous wife. The character even has the scar on her face she received fighting Man-Thing in the comics! So what does all this mean for a possible Man-Thing appearance in Phase Two? Only time will tell.